Optical element having stray light suppression structure

ABSTRACT

An optical element having stray light suppression structure includes a main body which is ring-shaped and defines an axial direction. The main body has an inner peripheral face and an outer peripheral face. The main body is for being arranged inside a lens mount. The main body has a first end and a second end along the axial direction and has plural stray light suppression structures on the inner peripheral face. The stray light suppression structures are spacedly arranged around the axial direction. A surface of each stray light suppression structure is non-coplanar with the inner peripheral face. Each stray light suppression structure has a third end closer to the first end and a fourth end closer to the second end. Each stray light suppression structure has an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to m optical element having stray light suppression structure.

Description of the Prior Art

An optical device such as lens assembly is composed of a plurality of optical elements such as lens, spacer ring, or positioning ring. Because only part of the lens can be used for imaging, stray light is generated when light hits the position which is not optical portion. Stray light may reduce the performance of imaging.

To avoid the stray light, rough surface is usually used to disperse light, as shown in patents TW 1612354, TW 1616697, and TW 1639029. The rough surface is formed around the optical portion or on the inner peripheral face of the spacer ring.

However, the bumps or recesses have even shapes. For example, concentric annular grooves or radial linear grooves are often used. The surface for reflecting has a specific orientation. Sometimes the surface concentrates the stray light instead.

SUMMARY OF THE INVENTION

The main object of the present invention is to provide an optical element having stray light suppression structure to prevent imaging from being affected by stray light.

To achieve the above and other objects, the optical element having stray light suppression structure of the present invention includes a main body. The main body is ring-shaped and defines an axial direction. The main body has an inner peripheral face and an outer peripheral face. The main body is adapted for being arranged inside a lens mount wherein the outer peripheral face of the main body connects to an inner wall of the lens mount. The main body has a first end and a second end along the axial direction. The main body has a plurality of stray light suppression structures on the inner peripheral face. The stray light suppression structures are spacedly arranged around the axial direction. A surface of each of the stray light suppression structures is non-coplanar with the inner peripheral face. Each of the stray light suppression structures has a third end closer to the first end and a fourth end closer to the second end. Each of the stray light suppression structures has an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.

To achieve the above and other objects, the optical element having stray light suppression structure includes a main body. The main body defines an axial direction. The main body has an optical portion at a center thereof. The main body further has a dispersing portion surrounding the optical portion. The main body has a plurality of stray light suppression structures on the dispersing portion. The stray light suppression structures are spacedly arranged around the axial direction. A surface of each of the stray light suppression structures is non-coplanar with the dispersing portion. Each of the stray light suppression structures has a third end closer to the optical portion and a fourth end remote from the optical portion. Each of the stray light suppression structures has an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.

The present invention will become more obvious from the following description when taken in connection with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment(s) in accordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a stereogram of the present invention;

FIG. 2 is a breakdown drawing of the present invention;

FIG. 3 is a profile of the present invention;

FIG. 4 is an illustration showing paths of stray lights of the present invention;

FIG. 5 is a partial stereogram of the present invention;

FIG. 6 is a partial stereogram showing a second embodiment of the present invention;

FIG. 7 is a partial stereogram showing a third embodiment of the present invention;

FIG. 8 is a partial stereogram showing a fourth embodiment of the present invention;

FIG. 9 is a partial stereogram showing a fifth embodiment of the present invention;

FIG. 10 is a partial stereogram showing a sixth embodiment of the present invention;

FIG. 11 is a partial stereogram showing a seventh embodiment of the present invention;

FIG. 12 is a partial stereogram showing an eighth embodiment of the present invention;

FIG. 13 is a partial stereogram showing a ninth embodiment of the present invention;

FIG. 14 is a front view showing a tenth embodiment of the present invention;

FIG. 15 is a partial stereogram showing a tenth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIG. 1 to FIG. 13, the optical element having stray light suppression structure of the present invention includes a main body 10,10 a,10 b,10 c,10 d,10 e,10 f,10 g,10 h, such as a positioning ring or a spacer ring 30). The main body 10,10 a,10 b,10 c,10 d,10 e,10 f,10 g,10 h is ring-shaped and defines an axial direction. The main body 10,10 a,10 b,10 c,10 d,10 e,10 f,10 g,10 h has an inner peripheral face 11 and an outer peripheral face 12. The main body 10,10 a,10 b,10 c,10 d,10 e,10 f,10 g,10 h is adapted for being arranged inside a lens mount 20 wherein the outer peripheral face 12 of the main body 10,10 a,10 b,10 c,10 d,10 e,10 f,10 g,10 h connects to an inner wall of the lens mount 20. The main body 10,10 a,10 b,10 c,10 d,10 e,10 f,10 g,10 h has a first end 101 and a second end 103 along the axial direction. The main body 10,10 a,10 b,10 c,10 d,10 e,10 f,10 g,10 h has a plurality of stray light suppression structures 13,13 a,13 b,13 c,13 d,13 e,13 f,13 g,13 h on the inner peripheral face 11. The stray light suppression structures 13,13 a,13 b,13 c,13 d,13 e,13 f,13 g,13 h are spacedly arranged around the axial direction. A surface of each of the stray light suppression structures 13,13 a,13 b,13 c,13 d,13 e,13 f,13 g,13 h is non-coplanar with the inner peripheral face 11. Each of the stray light suppression structures 13,13 a,13 b,13 c,13 d,13 e,13 f,13 g,13 h has a third end closer to the first end 101 and a fourth end closer to the second end 102. Each of the stray light suppression structures 13,13 a,13 b,13 c,13 d,13 e,13 f,13 g,13 h has an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.

In the present embodiment, each of the stray light suppression structures 13,13 a,13 b is S-shaped and is a groove, as shown in FIG. 5 to FIG. 7. However, in other embodiments of the present invention, each of the stray light suppression structures 13 f,13 g,13 h can be a V-shaped groove, as shown in FIG. 11 to FIG. 13. Preferably, each of the stray light suppression structures 13 f,13 g,13 h includes two segments connected together. An angle between the two segments is larger than 180 degrees or smaller than 180 degrees. Each of the stray light suppression structures 13 c,13 d,13 e can be zigzag groove, as shown in FIG. 8 to FIG. 10. Preferably, each of the stray light suppression structures 13 c,13 d,13 e includes at least three segments connected sequently. An angle between any two adjacent ones of the segments is larger than or smaller than 180 degrees.

In view of the shape of the groove, in the present embodiment, the groove (the stray light suppression structure 13,13 c,13 f) has a radial cross-section which is trapezoid narrower at the opening and wider at the bottom, as shown in FIG. 5, FIG. 8, and FIG. 11. (A rib is formed between any two adjacent grooves, and the rib has a radial cross-section which is also trapezoid narrower at the top thereof) In other possible embodiments, the groove (the stray light suppression structure 13 a,13 d,13 g) has a radial cross-section which is reversed triangle, as shown in FIG. 6, FIG. 9, and FIG. 12. (A rib is formed between any two adjacent grooves, and the rib has a radial cross-section which is triangle.) The groove (the stray light suppression structure 13 b,13 e,13 h) can have a radial cross-section at the bottom which is concave arc-shaped, as shown in FIG. 7, FIG. 10, and FIG. 13. (A rib is formed between any two adjacent grooves, and the rib has a radial cross-section which is convex arc-shaped.)

As shown in FIG. 14 and FIG. 15, the present invention further provide an optical element having stray light suppression structure includes a main body 10′, such as a lens. The main body 10′ defines an axial direction. The main body 10′ has an optical portion 14 at a center thereof for light passing to image. The main body 10′ further has a dispersing portion 15 surrounding the optical portion 14. The main body 10′ has a plurality of stray light suppression structures 13 on the dispersing portion 15. The stray light suppression structures 13 are spacedly arranged around the axial direction. A surface of each of the stray light suppression structures 13 is non-coplanar with the dispersing portion 15. Each of the stray light suppression structures 13 has a third end closer to the optical portion 14 and a fourth end remote from the optical portion 14. Each of the stray light suppression structures 13 has an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.

In the present embodiment, each of the stray light suppression structures 13 is S-shaped groove, and the groove (the stray light suppression structure 13) has a radial cross-section which is trapezoid narrower at the opening and wider at the bottom. However, as mentioned above, each of the stray light suppression structures can be V-shaped, zigzag, or other shape which is not linear, and the radial cross-section of the groove can be arc-shaped, reversed triangle, or other shape.

In use, as shown in FIG. 4, when the optical element is disposed inside the lens mount and the lens assembly is operated for imaging, the stray light suppression structures 13 provides a lot of faces which are not parallel to the inner peripheral face of the main body to reflect the stray light, and the stray light suppression structure 13 is not linear to provide faces in different orientations for reflect stray light in more directions. Thus, the stray light can be dispersed better to give a better image.

In conclusion, the optical element of the present invention has stray light suppression structures which are not linear so as to provide reflection faces in more orientations. Thereby, the stray light can be dispersed better, and the lens assembly can provide better images. 

What is claimed is:
 1. An optical element having stray light suppression structure, including a main body, the main body being ring-shaped and defining an axial direction, the main body having an inner peripheral face and an outer peripheral face, the main body being adapted for being arranged inside a lens mount wherein the outer peripheral face of the main body connects to an inner wall of the lens mount, the main body having a first end and a second end along the axial direction, the main body having a plurality of stray light suppression structures on the inner peripheral face, the stray light suppression structures being spacedly arranged around the axial direction, a surface of each of the stray light suppression structures being non-coplanar with the inner peripheral face, each of the stray light suppression structures having a third end closer to the first end and a fourth end closer to the second end, each of the stray light suppression structures having an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.
 2. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is V-shaped.
 3. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is S-shaped.
 4. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is zigzag.
 5. The optical element having stray light suppression structure of claim 2, wherein each of the stray light suppression structures includes two segments connected together, an angle between the two segments is larger than or smaller than 180 degrees.
 6. The optical element having stray light suppression structure of claim 4, wherein each of the stray light suppression structures includes three segments connected sequently, an angle between any two adjacent ones of the segments is larger than or smaller than 180 degrees.
 7. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is a groove, a bottom of the groove has a radial cross-section which is concave arc-shaped.
 8. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is a groove, the groove has a radial cross-section which is reversed triangle.
 9. The optical element having stray light suppression structure of claim 1, wherein each of the stray light suppression structures is a groove, the groove has a radial cross-section which is trapezoid narrower at an opening and wider at a bottom.
 10. An optical element having stray light suppression structure, including a main body, the main body defining an axial direction, the main body having an optical portion at a center thereof, the main body further having a dispersing portion surrounding the optical portion, the main body having a plurality of stray light suppression structures on the dispersing portion, the stray light suppression structures being spacedly arranged around the axial direction, a surface of each of the stray light suppression structures being non-coplanar with the dispersing portion, each of the stray light suppression structures having a third end closer to the optical portion and a fourth end remote from the optical portion, each of the stray light suppression structures having an extension path at least partially nonoverlapping a line defined from the third end to the fourth end.
 11. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is V-shaped.
 12. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is S-shaped.
 13. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is zigzag.
 14. The optical element having stray light suppression structure of claim 11, wherein each of the stray light suppression structures includes two segments connected together, an angle between the two segments is larger than or smaller than 180 degrees.
 15. The optical element having stray light suppression structure of claim 13, wherein each of the stray light suppression structures includes three segments connected sequently, an angle between any two adjacent ones of the segments is larger than or smaller than 180 degrees.
 16. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is a groove, a bottom of the groove has a radial cross-section which is concave arc-shaped.
 17. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is a groove, the groove has a radial cross-section which is reversed triangle.
 18. The optical element having stray light suppression structure of claim 10, wherein each of the stray light suppression structures is a groove, the groove has a radial cross-section which is trapezoid narrower at an opening and wider at a bottom. 